minor: translate "Save as epub" and "Close" in full Wikipedia window (#2875)
minor: translate "Save as epub" and "Close" in full Wikipedia window (#2875)

* translate save as epub and close

* epub to EPUB

mihailim/koreader,robert00s/koreader,Markismus/koreader,apletnev/koreader,NiLuJe/koreader,NiLuJe/koreader,lgeek/koreader,koreader/koreader,Frenzie/koreader,houqp/koreader,pazos/koreader,mwoz123/koreader,Frenzie/koreader,poire-z/koreader,koreader/koreader,poire-z/koreader,Hzj-jie/koreader